#!/bin/bash

# 检测参数是否为hello，如果是显示hello,how are you，如果没有参数，提示，不是则提示只能用hello

if [ -z "$1" ]; then
    echo "You must input parameter."
elif [ "$1" == "hello" ]; then
    echo "Hello, how are you?"
else
    echo "Please use 'hello' as parameter"
fi

if [ "$2" == "" ]; then
    echo "parameter \$2 is empty"
fi

